I found this business card in my stack of visited places & art shows. If you go to the Of Nature Website, you can see the detailed, copper-clad little nature masterpieces.
Each tiny work of art is an actual item from the woods, carefully preserved and coated in copper. A patina (chemical that reacts with copper to change color) is applied to the metal. Patinas are hand mixed, then layered to achieve the desired result. Ofnature also has an Etsy shop, making it easy to purchase.